Some typical applications of capacitors include: 1. Filtering:Electronic circuits often use capacitors to filter out unwanted signals. For example, they can remove noise and ripple from power supplies or block DC signals while. A capacitor is a passive electrical device that stores electrical energy in an electric field. It consists of two conductive plates separated by an insulating material called the dielectric. The plate. In short, capacitors have various applications in electronics and electrical systems. They are used in power supply circuits to smooth out. Capacitors used for suppressing undesirable frequencies are sometimes called filter capacitors. They are common in electrical and electronic equipment, and cover a number of applications, such as: • Glitch removal on (DC) power rails• (RFI) removal for signal or power lines entering or leaving equipment.